collection interval

collection jitter

Collection jitter is used to prevent every input plugin from collecting metrics simultaneously, which can have a measurable effect on the system.
Each collection interval, every input plugin will sleep for a random time between zero and the collection jitter before collecting the metrics.

flush jitter

Flush jitter is used to prevent every output plugin from sending writes simultaneously, which can overwhelm some data sinks.
Each flush interval, every output plugin will sleep for a random time between zero and the flush jitter before emitting metrics.
This helps smooth out write spikes when running a large number of Telegraf instances.

input plugin

Input plugins actively gather metrics and deliver them to the core agent, where aggregator, processor, and output plugins can operate on the metrics.
In order to activate an input plugin, it needs to be enabled and configured in Telegraf’s configuration file.

metric buffer

The metric buffer caches individual metrics when writes are failing for an output plugin.
Telegraf will attempt to flush the buffer upon a successful write to the output.
The oldest metrics are dropped first when this buffer fills.

precision

The precision configuration setting determines how much timestamp precision is retained in the points received from input plugins. All incoming timestamps are truncated to the given precision.
Telegraf then pads the truncated timestamps with zeros to create a nanosecond timestamp; output plugins will emit timestamps in nanoseconds.
Valid precisions are ns, us or µs, ms, and s.

For example, if the precision is set to ms, the nanosecond epoch timestamp 1480000000123456789 would be truncated to 1480000000123 in millisecond precision and then padded with zeroes to make a new, less precise nanosecond timestamp of 1480000000123000000.
Output plugins do not alter the timestamp further. The precision setting is ignored for service input plugins.

service input plugin

Service input plugins are input plugins that run in a passive collection mode while the Telegraf agent is running.
They listen on a socket for known protocol inputs, or apply their own logic to ingested metrics before delivering them to the Telegraf agent.